Polycarboxy acid esters of oxypropylated sulfides



United States Patent POLYCARBOXY ACID ESTERS OXYPRQ- 'PYLA'TED TSULFIDES Melvin De Greene, St. Louis, Mo., assignor to Petrolite Corporation, a corporation of Delaware No Drawing. Original application December 1, .1950, Se-

rial No. 198,752 now Patent No. 2,626,924, dated January "27, I953. Divided and this application De- 'cemb'erz, 1952, Serial No. 323,728

r 8 Claims. ((11. 260-475) 7Bhe present invention is concerned with certain .new chemical products,cornpoundsor compositions which have useful application in various arts.

The particular compounds subsequently described here- .in in greater detail are hydrophile synthetic products, and more ;.particularl-y, :fra'ctional esters obtained from -a polycarboxy acid and a sulfur-containing diol obtained by the oxypropylation of sulfur-containing compounds in which there are present two members .selected'from the class of OHand SH radicals, i. e., hydroxyl radicals and thio radicals in the sense that the alkyl mercaptans or similar compounds are also designated as alkane thiols. There is the .further ,proviso that such sulfur-containing compound be free from any radical having 8 or more carbon .atoms in a single uninterrupted group and the di- Ihydroxylated compound prior to esterification must be water-insoluble and kerosene-soluble. Numerous sulfurcontaining compounds susceptible to 'oxypropyla'tion or, iorfthat matter, to 'oxyethylation are well :known. The one which .I prefer to use is Z-mercaptoethanol, also the product .known as thiodiethylene glycol, thiodiglycol, or di12-hydroxyethyl sulfide. Just as satisfactory, of course, is the resultant compound obtained by treating 2-'mercaptoethanol with one, two or three moles of ethylene oxide.

"'Phepr'oducts of this invention have particular value as demnl'sifying agents in a process for resolving petroleum emulsions of the water-in-oil type that are commonly referred to as cut oil, roily oil, emulsified oi1,-etc., and which comprise fine droplets of naturally-occurring waters orbrines dispersedin a more or less permanent .state throughout the oil which constitutes the continuous phase of the emulsion. A process for resolvinggpetroleurn emulsions of the water-in-oil type which utilizes the prod ucts described hereintis described and'claimed in my copending application Serial No. 198,752, filed December 1, 1950, now Patent 2,626,924, granted January 27, 1953.

The products 'are'also useful in a process for separating emulsions which have been prepared under controlled conditions from mineral oil, such as crude oil and relatively soft Waters or weak brines. Controlled emulsification and subsequent .demulsification under the conditions just mentioned are of significant value in removing :im purities, particularly inorganic salts from pipeline oil. They are also useful for other purposes, such as stabilizing emulsions, as Spreaders in the application of asphalt in road building and the like, as flotation .reagents, as lubricants, etc.

v 2,743,293 Patented Apr. 24, 1956 For convenience what is said hereinafter will be divided into four parts:

Part 1 will be concerned with the oxypropylation of the specified sulfur-containing compound;

Part 2 will be concerned with the preparation of the esters from the oxypropylated compounds;

'Part 3 will be concerned with the structure of the oxypropylated compounds obtained from the specified'sulfur-containing initial materials; and

Part 4 will be concerned with certain derivatives'whi'ch can be obtained from the diols of the aforementioned type. In some instances such derivatives are obtained by modest oxyethylation preceding "the oxypropylation step, or oxypropylation followed by oxyet'hylation. This results in diols having somewhat ditierent properties which can then be reacted with the same polycarboxy acids or anhydri'des described in Part .2. .For this :reason a description of the apparatus makes casual .mention of oxyethylation. For the same .reason there is brief Intention of the use of gl-ycide.

PART 1 For a number of well known reasons equipment, whether laboratory size, semi-pilot plant size, pilot plant size, or large-scale size, is not as a rule designed for a particular 'alkylene oxide. Invariably and inevitably, however, or particularly in the case of'labora'tory equipment and pilot plant size the design is such as to use any of the customarily available alkylene oxides, i. e., ethylene oxide, propylene oxide, butylene oxide, glycide, epichlorohydr'in, styrene oxide, etc. 'In the subsequent description of the "equipment it becomes obvious that it is adapted for oxyethylation as well as 'oxypropylation. The procedures used fo'r'the oxypropylation operation'are substantially the same as those 'conventionallyused in carrying out 'oxypropylations, :and 'for this reason, the oxypropylation step will simply the illustrated by the 'following specific examples.

Example I a The starting material was a commercial grade of 2.- niercaptoethanol. Thesparticular autoclaveemployed was one with a capacity of .15 "gallons or on the averageof .1 20 :pounds of reaction mass. The speed of the stirrer could be varied from to .350 R. P. M. 915 poundsbf Z-mercapto-ethanol were charged-into the autoclave along with one pound of caustic soda. The reaction pot was flushed out with nitrogen. The autoclave was sealed and the automatic devices adjusted :for injecting a total of slightly over '8 7 pounds of propylene oxide in ap proximately 3 /2 hours. The pressure regulator was set for a maximum of 35 to 37 pounds per square inch. This meant that the bulk of the reaction could take place and probably did take place at a =lower pressure. 'This comparatively low .pressure was the result of the fact that considerable catalyst was present. The propylene oxide was added comparatively slowly and, "more important, the selected temperature range 'was 220 to 225 'F. (just slightly above the boiling point of water). The initial introduction of propylene-oxide was .not started untilthe heating devices had raised the temperature to about the boiling point of water. At the completion of the reaction Example 2a, immediately succeeding.

Example 2a 66.5 pounds of the reaction mass identified as Example 10, preceding, were permitted to remain in the reaction vessel and without the addition of any more catalyst 43 pounds of propylene oxide were added. The oxypropylation was conducted in substantially the same manner with regard to pressure and temperature as in Example 1a, preceding, except that the reaction was complete in slightly less time, that is, 3 hours instead of 3 /2 hours. At the end of the reaction period part of the sample was withdrawn and oxypropylation continued as described in Example 30, following.

Example 3a 62.15 pounds of the reaction mass identified as Example 2a, preceding, were permitted to remain in the reaction vessel. 43 pounds of propylene oxide were introduced in the third stage. No additional catalyst was added. The time period required was the same as in thepreceding example, i. e., 3 hours. The conditions of reaction as far as temperature and pressure were concerned were substantially the same as in Example la, preceding. At the completion of the reaction part of the reaction mass was withdrawn and the remainder subjected to oxypropylation as described in Example 4a, following.

Example 4a Example 5a" Approximately 68.9 pounds of the reaction mass were permitted to stay in the autoclave. No additional catalyst was introduced. 27.5 pounds of propylene oxide were added. The time required to add this propylene oxide was 2% hours. The conditions of reaction in regard to temperature and pressure were substantially the same as in Example 111, preceding.

Example 6a Approximately 88.65 pounds of reaction mass were permitted to stay in the autoclave. No additional catalyst was introduced. 22 pounds of propylene oxide were added. The time required to add this propylene oxide was 3 /2 hours. The conditions of reaction in regard to temperature and pressure were substantially the same as in Example In, preceding.

What is said herein is presented in tabular form in Table 1 immediately following, with some added infor mation as to molecular weight and as to solubility of the reaction product in water, xylene, and kerosene.

In the above examples, 1a was emulsifiable in water, soluble in xylene, and dispersible in kerosene. The solubility of Examples 2a through 6a, inclusive, was identical in that they were all water-insoluble, all xylene-soluble, and all kerosene-soluble.

The products so obtained are liquids showing modest viscosity and perhaps a slight odor. In each instance there was some residual basicity due to the catalyst which, of course, would be true also if sodium methylate had been employed.

Speaking of insolubility in water or solubility in kerosene such solubility test can be made simply by shaking small amounts of the materials in a test tube with water, for instance, using 1% to 5% approximately based on the amount of water present.

Needless to say, there is no complete conversion of propylene oxide into the desired hydroxylated compounds. This is indicated by the fact that the theoretical molecular weight based on a statistical average is greater than the molecular weight calculated by usual methods on basis of acetyl or hydroxyl value. Actually, there is no completely satisfactory method for determining molecular weights of these types of compounds with a high degree of accuracy when the molecular weights exceed 2,000. In some instances the acetyl value or hydroxyl value serves as satisfactorily as an index to the molecular weight as any other procedure, subject to the above limitations, and especially in the higher molecular weight range. If any difiiculty is encountered inv the manufacture of the esters as described in Part2 the stoichiometrical'amount of acid or acid compound should be taken which corresponds to the indicated acetyl or hydroxyl value. This matter has been discussed in the literature and is a matter of common knowledge and requires no further elaboration. In fact, it is illustrated by some of the examples appearing in the patent previously mentioned.

PART 2 As previously pointed out the present invention is concerned with acidic esters obtained from the oxypropylated derivatives described in Part 1, immediately preceding, and polycarboxy acids, particularly dicarboxy acids such as adipic acid, phthalic acid or anhydride, succinic acid, diglycollic acid, sebacic' acid, azelaic acid, aconitic acid, maleic acid or anhydride, citraconic acid or anhydride, maleic acid or anhydride adducts as obtained by the Diels-Alder reaction from reactants such as maleic anhydride and cycl-opentadiene. Such acids should be heat stable so they are not decomposed during esterification. They may contain as many as 36 carbon atoms as, for example, the acids obtained by dimerization of unsaturated fatty acids, unsaturated monocarboxy fatty acids, or unsaturated monocarboxy acids having 18 carbon atoms. Reference to the acid in the hereto appended claims obviously includes the anhydrides or any other obvious equivalents. My preference, however, is to use polycarboxy acids having not over 8 carbon atoms.

The production of esters including acid esters (fractional esters) from polycarboxy acids and glycols or other hydroxylated compounds is well known. Needless to say, various compounds may be used such as the low molal ester, the anhydride, the acyl chloride, etc.

TABLE 1 Composition before Composition at end M W M I ax. by hyd g H pres, lbs. 52

' Sul. empd. Oxide Catalyst, Theo Sui. cmpd. Oxide Catalyst, determln. sq. in.

amt., lbs. amt., lbs. lbs. mol. wt amt., lbs. amt., lbs. lbs.

1a. 9. 5 1.0 l, 240 9. 5 87.12 1. 0 820 220225 35-37 3 2a. 6. 45 59. 12 68 2, 055 6. 45 102. 12 68 1, 218 220-225 35-37 3 31L 8. 66 58. 10 39 3, 490 3. 66 101. 10 39 1, 920 220-225 35-37 3 4a. 2. 13 58. 92 23 5, 980 2. 13 102. 30 23 3, 300 220-225 35-37 4 5a. 1. 40 67. 35 15 390 1. 40 94. 15 2, 900 220-225 35-37 2% 1. 29 87. 22 14 10, 470 1. 29 109. 22 14 3, 040 220-225 3537 3 1;

, V However, for purpose of economy it .is customary touse either the acid orthe anhydride. A conventionalprocedure is employed. '"On a laboratory scale one can emyploy "a resin pot of the kind described in U. S. l'Paten't No. 2,499,370, dated March .7 1950, to DeGroote & K'eiser, and particularly with one -more opening to permit the use of a porous spreader if hydrochloric acid gas is to be used as a cat-alyst. Such device'or absorptionspreader consists of minute Alundurn thimbles which are connected to a glass tube. Onecan add a sulfonic acid such as para-toluene sulfonic acid as a catalyst. There is some objection to this because fin some instances there is some evidence that this acid catalyst tends to decompose or rearrange oxypropylated compounds, and particularly likely to do so if theresterification temperatureis'too'high. In the case of polycarboxy-acids'such astdiglycollic acid, which is strongly acidic thereisno need .to-add any catalyst. The use of hydrochloric gas .has one advantage over paratoluene sulfonic .acidand that is thata't the end of the reaction it :can be removed .byIflushing out with nitrogen, whereas .there is no reasonably 'convenielnt means available of removing the paratoluene sulfonic acid or other sulfonic acid employed. If hydrochloric acid is employed one need only pass .the gas through at an exceedinglyslow rateso as to keep'thereaction mass acidic. Only a trace of acid need be ,present. I .have employed hydrochloric acid gas or -the aqueous acid itself to eliminate the initial basic material. MY Preference, however, is to use no catalyst whatsoever and to insure complete dryness of the diol as described in the final procedure just preceding Table 2. i

The products obtained in Part 1 ,preceding may contain a basic catalyst. As a general "procedure I have added an amount of half-concentrated hydrochloric acid \considerably in ECXCQSS of what is required to neutralize the residual catalyst. The mixture :is shaken thoroughly and allowed to stand overnight. It is then :filtered and sreliuxed with .the xylene present until the "water :can be separated in a phaseeseparating .trap. -As soon as the product is substantially .free vfrom water the distillation :stops. .This preliminary step can be carried out in the flask rto he used .for .esterification. If there is any fur- .therdepositionof sodiurnchloride duringthe reflux stage needless.to:say asecond filtration-may berrequire d. in any event .the .neutral .or :slightly acidic solution of the ,oxypropylated derivatives :described in Part 1 .is vthen di- .luted .further .with :suflicient .Xylene, decalin, petroleum solvent, .or the like, so that one .has obtained approximatelya 45% :solution. To this-solution .there .is added -.-.a,polycarboxylated reactant as previously described, such .as-phthalic anhydride, succinicacid or anhydride, 'diglycollie-acid, etc. The mixture is refluxed until vesterificationsis complete .as indicated by elimination of water or drop .in carboxyl value. Needless .tosay, .if one produces a half-ester from an anhydride such as .phthalic anhydride, .no water :is :eliminated. However, if it is obtained from :diglycollic acid, .for example, .water is veliminated. .All .such procedures are conventional and have heen-so thoroughly -.described.in the literature that iurther-consideration will be limited to .a few examples and a comprehensive table.

.Qther procedures v.for eliminating the basic residual catalyst, ifany, tcan .beemployed. .For example, the oxyalkylation.eanbe-conductedinabsence of a solvent or the .solxent removed after oxypropylation. Such oxypropylation .end product can then :be acidified with just enough concentrated hydrochloric acid to just neutralize ttheafesidualahasic catalyst. To this product :cne :canithen add a small amount of anhydrous sodium sulfate (5suffficien't quantity to take up any Water that is present) and then subject the mass to centrifugal force so as to eliminate the hydrated sodium sulfate and probably the sodiinn chloride formed. The clear "somewhat viscous straw-colored amber liquid so obtained may contain a small amount of sodium sulfate or sodium chloride but,

in "anyevent, is perfectly acceptable for 'esterificationiin the manner described.

Itis to be pointed out that the productshere described are not polyesters in the sense that there is a plurality of both "diol "radicals and acid radicals; "the product is characterized by having only one diol radical.

In 'some instances and, in fact, in many instances 1 have found that in spite of the dehydration methods-employed above that a mere trace of water still comes through-and that this mere trace "of waterfcertainly interferes with the .acetyl .orihydr'oxyl value determination, at least when a number of conventional procedures are used and may retard esterification, particularly where there is no sul'fonic :acid or hydrochloric acid present as a catalyst. Therefore,'I have preferred to use the following procedure: 'I have employed about 200 grams of the diol as zdescribedsin Part 11, :preceding; I have added about 60 grams of benzene, and then refluxed this mixture in the :glass resin pot using a phase-separating trap until :the benzene carried out all the water present as water of .solution or :the equivalent. Ordinarily this refluxing temperature is apt to be in the neighborhood of 130 to possibly 150 C. When all this water or moisiture has 'been removed I also withdraw approximately 20 grams or a little less benzene and then add the required amount of the carboxy :reactant and also about 1.50 grams-of a high boiling aromatic petroleum solvent. These solvents are sold by various oil refineries and, as far as solvent eifectiact as if they were almost completely aromatic in character. Typical distillation data in the particular type I have employed and found very satisfactory is the following:

I.\B.P.,142 c. 5 nil., 200 c.

10 ml., 209 c. m1.,"21s 'c. m1.,.216 c. ml, 220C. ml., 225C. 3'5 rril., 230 c. ml., 234 c. 90 ml., 280 0. ml., 237 c. 95 mL, 307C.

After this material is added, refluxing is continued, and, of course, is at a high temperature, to wit, about 160 to 170 C. If the carboxy reactant is an anhydride needless to say no water of reaction appears; if the carboxy reactant is an acid water ofreaction should appear and should be'eliminated at the above reaction temperature. If it is not eliminated I simply separate out another '10 to 20 cc. of benzene by means of the phase-separating trap and :thus raise the temperature to 1'80" or 190 C., or even to 1200 C., if need be. My preference is not to :go above 200 C.

The use of such solvent is extremely satisfactory provided one does not attempt to remove the solvent subsequently except by vacuum distillation and provided there is .no objection to a little residue. Actually, when these materials are used for a purpose such as demu'lsification the solvent might just as well be allowed to remain. if the solvent is to be removed by distillation, and particularly vacuum distillation, then the high boiling aromatic petroleum solvent might We'll be replaced by some more expensive solvent, such as 'd'e'c'alin or an alkyl'ated 'decalih which has a rather definite or close range boiling point. The removal of the solvent, of course, is purely a conventional procedure and requires noel'aboration.

'In the appended table solvent #7-3, which appears in all instances, is afmixture of 7 volumes of the aromatic petroleum solvent previously describe'd'and 3vo1urnes of benzene. This 'was used, or a similar mixture, in the mannerpreviously described. In a large number of similar examples decalin *has been used but "it is my preference to use the abovementioned mixture and ,pa'r'ticulaflywit'h the preliminary step ofremoving all ihewater. If one 'doesnot intend to remove the solvent my prefml, 242 ,C. ml, 244 'C. ml., 248 C. ml., 252* C. 1111., 252 c. ml., 260 "C. ml., 264 C. ml, 270 C.

erence is to use the petroleumsolvent-benzene mixture although obviously any of the other mixtures, such as decalin and xylene, can .be employed.

The data included in the subsequent tables, i. e., Tables salt should be eliminated, at least for exploration experimentation, and can be removed by filtering. Everything else being equal as the size of the molecule increases the reactive hydroxyl radical represents a smaller fraction 2 and 3, are self-explanatory, and very complete and it is of the entire molecule and thus more difiiculty is involved believed no furtherelaboration is necessary: in obtaining complete estei'ification.v

TABLE 2 i Amt of v Theo. Theo. Ev- M01. wt. Amt. of Ex. of Ex. No. Actual polycaractid of org. b? 7 2 hydiiosyl 1723523 3 3 Polycarboxy reactant boxy t as at cmp ya no teac an H. O H. C II. V. (grs.) (grs) 1b 1a 1, 240 90. 6 137 820 200 Diglyoollic acid 1. 64. 2 1a 1, 240 00. 5 137 320 200 Phthalic anhyd 71. 0 3b 1a 1, 240 00. 5 137 320 200 Malelo anhyd 47. 3 45 1c 1, 240 90. 5 137 320 201 Oltraconic act 55. 0 55 la 1, 240 00. 5 137 520 204 Aconitle acid 85. 5 6b 212 2,055 54. 6 92. 3 1, 218 205 Diglycollic ac 45. 5 7b 2a 2, 055 54. 5 02. 3 1,213 200 Phthalic anhyd 50. 5 3b 211 2,055 54.5 22.3 1,213 205 Maleic anhyd 33.0 911 211. 2,055 54.5 92.3 1, 218 204 Aconitic acid 58.1 105 2a 2, 055 54. 0 02. 3 1, 213 205 Oitracom'c acid 37. 3 11b 50. 3, 490 32. 2 58. 5 1, 920 202 Dtglycollic acid- 28. 2 12b 32 3, 400 32. 2 53. 5 1, 020 209 Phthalic anhyd. 32.2 130 3a 3, 400 32.2 53. 5 1,920 207 Maleic anii d. 21. 2 140 3a 3, 400 32. 2 53. 5 1, 020 205 Aconitlc acid. 37. 2 150 3a 3, 400 32. 2 5s. 5 1, 020 200 Oiiraconic acid 24. 0 150 4c 5, 930 13. s 34. 0 3, 300 203 Diglycollic acid 1s. 2 17b 40 5, 030 18. s 34. 0 3,300 208 Phthalic anhyd 18. 5 18b 45 5, 950 18.8 34. 0 3, 300 207 Maleic anii d 12.3 19b 40 5, 980 is. s 34. 0 300 202 Acoru'tic acid 21. 2 205 45 5,980 18. s 34.0 3, 300 207 Citraconic acid 14 1 21b 5a ,390 13.4. 38. 5 2, 900 19s Diglycollic acid 18. 3 22b 52 3, 390 13. 4 33. 5 2, 000 202 Phtllalic anhyd 20. 5 23b 5a 3, 390 13. 4 3s. 5 2, 900 203 Maleic anhyd 13. 7 240 5a 8, 390 13.4 as. 5 2, 000 201 Aconitic acid 24. 1 25b 52 3, 390 13. 4 3s. 5 2, 900 209 Gitraconlc acid 15.1 26!) 601 10,470 10. 7 35. 0 3, 040 202 Dlglycollic acid- 17. 8 27!) 6a 10,470 10.7 35.9 3,040 210 Phthalic anhyd.-. 20.4 28!) Ga 10, 470 10. 7 35. 0 3, 040 205 Malelc anhyd... 13. 1 2% 6a 10,470 10.7 35. 9 3, 040 205 Aconltic acid.. 23. 4 30b 62 10,470 10.7 35. 0 3, 040 207 Gitracoinc acid 15. 2

TABLE 3 Even under the most carefully controlled conditions of oxypropylation involving comparatively low temperatures 1 Time 01 Ex, No of s t Aint. i01- gsteilficaestmflca Wmmut and long time of react on there are formed certain corn acid ester 7811 1011 on m pounds whose compositions are still obscure. Such side (11m) 40 reaction products can contribute a substantial proportion of the final cogeneric reaction mixture. Various suggesig 3-? tion have been made as to the nature of these compounds, #7-3 247 153 1 N01... such as being cyclic polymers of propylene oxide, dehydration products with the appearance of a vinyl radical,or #7-3 245 155 1% 5.5 isomers of propylene oxide or derivatives thereof, i. e., 33g :2 of an aldehyde, ketone, or allyl alcohol. In some instances #7-3 255 155 1%4 5.3 an attempt to react the stoichiometric amount of a polyfgj' V 1 carboxy acid with the oxypropylated derivative results in #7-3 2 41 155 2% 0. 2 an excess of the carboxylated reactant for the reason that :fgjg 55g 2 apparently under conditions of reaction less reactive hy- -3 23 0 157 115' None droxyl radicals are present than indicated by the hydroxyl 1Q lg? 352, value. Under such circumstances there is simply a residue #7-3 210 155 2 N one of the carboxylic reactant which can be removed by filtraigjg 4 A i tion or, if desired, the esterification procedure can be re- #73 213 iso 3 2. 3 peated using an appropriately reduced ratio of carboxylic #7-3 223 104 2% None reactant #7-3 217 154 2 Ioi'ie :7-5 12 3 2 0 Even the determination of the hydroxyl value by con- 218 153 2 ventional procedure leaves much to be desired due either fiZ-g fig g to the cogeneric materials previously referred to, or for 227 3 2 4 that matter, the presence of any inorganic salts or #7 2 158 2 N one propylene oxide. Obviously this oxide should be eliminated.

The procedure for manufacturing the esters has been illustrated by preceding examples. If for any reason reaction does not take place in a manner that is acceptable, attention should be directed to the following details: (a) Recheck the hydroxyl or acetyl value of the oxypropylated products of the kind specified and use a stoichiometrically equivalent amount of acid; (b) if the reaction does not proceed with reasonable speed either raise the temperature indicated or else extend the period of time up to 12 or 16 hours if need be; (c) if necessary, use /2 of paratoluene sulfonic acid or some other acid as a catalyst; (d) if the esterification does not produce a clear product a check should be made to see if an inorganic salt such as sodium chloride or sodium sulfate is not precipitating out. Such distillation. The final products or liquids are generally The solvent employed, if any, can be removed from the finished ester by distillation and particularly vacuum yellowish amber, pale'straw, or a deeper straw, in color, and show moderate viscosity. They can be bleached with bleaching clays, filtering chars, and the like. However, for the purpose of demulsification or the like color is not a factor and decolorization is not justified.

In the above instances I have permitted the solvents to remain present in the final reaction mass. In other instances I have followed the same procedure using decalin or a mixture of decalin or benzene in the same manner and ultimately removed all the solvents by vacuum distillation. Appearances. of the final products are much the .9 same as thediols beforeesterificationandinsomeinstances were somewhat darker .in color and had :a more. reddish .cast andperhapssomewhatmore viscous.

PARTS Diols (sulfur-free compound) such as polypropylene glycol of approximately 2,000 molecular weight, for example, have been esterified with dicarboxy acids and employed as demulsifyingta gents. 'Ihe herein described compounds are difierentfrom such ,diols although both,

"it is true, are high molecular weight .dihydroxylated comanalogy. Regardless .of .what the difference maybe the factstill remains that the compounds of tthekindherein .describedrnay be,.and flrequentlyare, .15 or 20% better on a quantitative'bas'is than the simplercompound previously described, .and .demnlsifyfaster. and .givecleaner oil in many instances. The method of makingsuchmomparative tests has been described in a booklet entitled Treating Oil Field Emulsions, used in the Vocational Training Course, Petroleum Industry Series, of the American Petroleum Institute.

It may be well to emphasize also the fact that oxypropylation does not produce a single compound but a cogeneric mixture. The factor involved is the same as appears if one were oxypropylating a monohydric alcohol or a glycol. Momentarily, one may consider the structure of a polypropylene glycol, such as polypropylene glycol of 2000 molecular weight. Propylene glycol has a primary alcohol radical and a secondary alcohol radical. In this sense the building unit which forms polypropylene glycols is not symmetrical. Obviously, then, polypropylene glycols can be obtained, at least theoretically, in which two secondary alcohol groups are united or a secondary alcohol group is united to a primary alcohol group, etherization being involved, of course, in each instance.

Usually no effort is made to difierentiate between oxypropylation taking place, for example, at the primary alcohol unit radical or the secondary alcohol radical. Actually, when such products are obtained, such as a high molal polypropylene glycol or the products obtained in the manner herein described one does not obtain a single derivative such as HO(RO)11,H in which n has one and only one value, for instance, 14, or 16, or the like. Rather, one obtains a cogeneric mixture of closely related or touching homologues. These materials invariably have high molecular weights and cannot be separated from one another by any known procedure without decomposition. The properties of such mixture represent the contribution of the various individual members of the mixture. On a statistical basis, of course, n can be appropriately specified.

This may be illustrated as follows: Assume that in any particular example the molal ratio of the propylene oxide to Z-mercaptoethanol or other selected sulfur compounds as specified is 30 to 1. Actually, one obtains products in which n probably varies from 10 to 20, perhaps even further. The average value, however, is 15, assuming, as previously stated, that the reaction is complete. The product described by the formula is best described also in terms of method of manufacture.

PART 4 2-mercaptoethanol, or other suitable sulfur-containing compound as specified herein, can be reacted with ethylene oxide in modest amounts and then subjected to oxypropylation provided that the resultantderivativeiis ,j(.a') water-insoluble, (b) kerosene-soluble, and (d) has present 15 to alkylene oxide radicals. Needless to say, in order to .have .water-insolubility .and .kerosenessolubility rthfi large .majority mustbepropylene .oxide. Other vari .ants suggest themselves .as, for example, replacing propylene-.oxideby.hutyleneoxide.

More specifically, one mole .of lunercaptoethanol .can be treated with .1, ,2 or .3 moles of ethylene .oxide .and then treated with propylene .oxide so as .to produce .a water-insoluble, kerosene-soluble \oxyallcylated ,product -in which there are present 15 to 80 oxide radicals as previ ously specified. Similarly the propylene oxide can be added first and then the ethylene oxide, or random oxyalkylation can be employed using a mixture of the two oxides. Thecompoundsso obtained are readily esterified in the same manner as described in Part 2, preceding. incidentally, the diols described in Part 1 or the modifications described therein can be treated w'ithvarious reactants such as g'lyc'ide, epichloroh'ydrin, "dime'thyl sulfate, sulfuric acid, maleic anhydride, ethylene imine, etc. If treated with epichlorohydrin or monochloroacetic acid the resultant product can be further reacted with a tertiary .amine such .as pyridine, for ithe like," to give uaternary ammonium compounds. .If treated ,with

maleic anhydride to give a total ester the resultant can.

be treated with sodium bisulfite to yield a sulfosuccinate. Sulfo groups can be introduced also by means of a sulfating agent as previously suggested, or by treating the chloroacetic acid resultant with sodium sulfite.

I have found that if such hydroxylated compound or compounds are reacted further so as to produce entirely new derivatives, such new derivatives have the properties of the original hydroxylated compound insofar that they are etfective and valuable demulsifying agents for resolution of water-in-oil emulsions as found in the petroleum industry, as break inducers in doctor treatment of sour crude, etc.

This application is a division of my copending appli cation Serial No. 198,752, filed December 1, 1950, now Patent 2,626,924, granted January 27, 3.

Having thus described my invention what I claim as new and desire to secure by Letters Patent, is

l. Hydrophile synthetic products; said hydrophile synthetic products being characterized by the following formula:

in which R is a divalent radical selected from the class consisting of -SC2H4O and in which x and x are integers, including 0, not greater than 3 and the sum of x and x is not greater than 3; and n and n are whole numbers with the proviso that n plus n equals a. sum varying from 15 to 80; n" is a whole number not over 2, and R is the radical of a polycarboxy acid selected from the group consisting of acyclic and isocyclic polycarboxy acids having not more than 8 carbon atoms and composed of hydrogen, carbon and oxygen of the formula /COOH in which n" has its previous significance, and with the further proviso that the parent dihydroxy compound prior to esterification be water-insoluble and kerosene-soluble.

2. Hydrophile synthetic products; said hydrophile synthetic products being characterized by the following formula:

in which R' is a divalent radical selected from the class consisting of '.-SC2H4O and than 3 and the sum of x and x is not greater than 3;

and n and n are whole numbers with the proviso that 11 plus n equals a sum varying from 15 to 80; and R is the radical of a dicarboxy acid selected from the group consisting of acyclic and isocyclic dicarboxy acids having not more than 8 carbon atoms and composed of hydrogen,"

carbon and oxygen of the formula C O OH COOH 12 n and n' are whole numbers withthe proviso that n plus. it equals a sum varying from 15 to and R is the radical'of a dicarboxy acid selected from the group con sisting of acyclic and isocyclic dicarboxy acids having not more than 8 carbon atoms and composed of hydrogen, carbon and oxygen of the formula with the further proviso that the parent dihydroxy compound prior to esterification be water-insoluble and kerosene-soluble. 4. The products of claim 3 wherein the dicarboxy acid is phthalic acid. p

5. The products of claim 3 wherein the dicarboxy acid is maleic acid.

6. The products of claim 3 wherein the dicarboxy acid is succinic acid.

7. The products of claim 3 wherein the dicarboxy acid is citraconic acid. p

8. The products of claim 3 wherein the dicarboxy acid is diglycollic acid.

' No references cited. 

1. HYDROPHILE SYNTHETIC PRODUCTS; SAID HYDROPHILE SYNTHETIC PRODUCTS BEING CHARACTERIZED BY THE FOLLOWING FORMULA: 